What I found is this:
With the update one of the updated files is assets/js/shapely-scripts.js
Line 97 to 114 deals with “// Fix nav to top while scrolling”
With the update to 1.2.2 it is embraced by an “if statement” (line 95 and the closing bracket in line 115. In version 1.2.1 the if statement was not there.
If you remove the “if statement” everything works normal.
I am not really happy with changing anything (and I mean it!) at the theme. So I would kindly ask you to consider if this needs to be looked at. Maybe the code does not actually produce what was intended?
Again, I do not want to confuse, I actually just want to help. If you say, this is not the solution, maybe you have something better?